The imminent flood of Facebook dollars is sure to provide a welcome boost to local businesses in Silicon Valley, from high-end car dealerships to wine merchants. Buff Giurlani, founder of car and wine storage service AutoVino in Menlo Park, is looking forward to an acceleration in already-brisk trade. “If a Facebook guy buys a house and wants to remodel it, maybe the contractor will buy another car,” he said. “Maybe the realtor will put a car in. There’s a trickle-down effect.”